Electrode support for cathode ray tubes



1941 K. WELLMANN arm. 2,231,146

ELECTRODE SUPPORT FOR CATHODE RAY TUBES Filed Dec. 15, 1937 I/w n 6 Patented Feb 11, 1941 UNITED STATES PATENT orrlcs ELECTRODE SUPPORT FOR CATHODE ,RAY TUBES Application December 15, 1937, Serial No. 180,016 In Germany December 17, 1936 2 Claims.

This invention relates to cathode ray tubes and particularly to an arrangement for supporting electrodes in such tubes.

It is known to fuse several parallel glass supports to the stem of a cathode ray tube, to adjust these accurately by means of a'gauge and to align the electrodes upon said glass supports. This method of support guarantees an accurate position of the electrodes at least in the plane perpendicular to the supports. The disadvantage of this arrangement is that the system can be incorporated only after completion of the stem and that the glass supports must be aligned with extraordinary accuracy.

In another known method of support these disadvantages are eliminated. According to this method the electrodes are first mounted upon a stand, or support, independent of the stem, and are aligned in respect to each other. In this 20, case the supporting body must have suificient accuracy as to guarantee the correct position of the electrodes. This increases the expense of production.

The present invention relates to a construction in which the electrodes are first put together and aligned independently of the stem, whereby, however, the expensive supporting body is eliminated. The system, which is in its entirety fastened to the stem, consists of the electrodes, and several connecting parts.

According to the invention the arrangement is so made that the electrodes and connecting parts mutually secure their position when put together by purely mechanical means without welding, soldering or fusing to glass, so that a rigid system is produced only after putting these parts together. The entire system is then fused to a stem, which stem is made in an independent operation.

Figures 1 and 2 of the drawing show an embodiment of the invention. In Fig. 1 the anode consists of a metal disc I, to which a cylinder 2 is welded, which disc is provided with a center aperture for the electron beam. 3 designates the deflecting plates for one direction of deflection, 4 the, deflecting plates for the other direction perpendicular to the first. All deflecting plates are provided with a flange, at the upper and lower ends, which serves supporting purposes, whereby the flanges and the plates are made as one unit. 5 and 6 are electrodes upon, which the fields of the plates end. The connecting parts are wholly isolating rods 1 which consist of ceramic material and which go through the apertures 8 and the electrodes or other flanges. The entire system obtains its mechanical rigidity only after assembly of the parts. The deflecting plates 3 and 4 are each supported by only two supports. Thus, if the other electrodes were not present the possibility would exist that the supports 1 would sufier a parallel displacement so that the cross section would no longer be a square but a parallelogram. Such a movement, however, is prevented by the discs I and 5, which are held by all four supporting rods 10 (Fig. 2, which shows only disc 5). On the other hand, the supports could be moved in respect to each other if the discs I and 5 alone were present. This, however, is later prevented by the deflecting plates. Thus, it may be seen that 15 in the present improved arrangement the electrodes are no longer fixed in their position by purely foreign means, but that they themselves are supporting members of the mechanical assembly.

The entire system thus obtained may now be pushed over two glass supports II] which are rigidly connected with a stem. For this purpose each of the discs I and 5 contains two opposite holes 9. The glass suppprts fused to the 25 stem may now be made with considerably less accuracy because the electrodes are already aligned. The electrodes may be attached to the supports by means of elastic rings, such as described in the co-pending application, Ser. No. 39 146,479, filed June 4, 1937, now matured into United States Patent No. 2,164,951,

We claim:

1. Electrode mounting for tubes of the oathode ray type comprising a plurality of disc-like 35 electrodes each being aper-tured at oppositely disposed points adjacent its periphery, a plurality of rods of insulating material extending through certain of said apertures with said disclike electrodes in spaced relationship on said 40 rods to provide a semi-rigid construction, a plurality of pairs of deflecting plates, each plate I having an integral flange at each end and apertured for mounting such deflecting plate across two of said supporting rods, each pair of de- 45 fleeting plates being thus supported on said rods normal to each other to rigidify said construction and provide an independent electrode assembly, a pair of assembly mounting members in said tube, said assembly mounting members 50 passing through a pair of said oppositely positioned apertures in said disc-like electrodes to support said rigid electrode assembly in said tube.

2. Electrode mounting for tubes' of the cathode ray type comprising a plurality of disc-like electrodes each apertured at oppositely disposed points adjacent its periphery, certain of such apertures being disposed at the corners of a rectangle, a plurality of rods of insulating material extending through said apertures located at the corners of said rectangle with said disclike electrodes in spaced relationship on said rods to provide a semi-rigid construction, a plurality of pairs of deflecting plates, each plate having an integral flange at each end and apertured for mounting such deflecting plate across KURT WEILMANN. ERWIN G'UNZEL. 

